1. Technical Field
This invention relates generally to sidewalls of rubber tires and, more particularly, to the structure of lettering or designs formed integrally in a tire sidewall. Specifically, the present invention relates to a structure for the lettering or design in a tire sidewall that increases the visibility and impact of the lettering or design by creating the impression on the viewer that the lettering or design is recessed into the tire sidewall without actually having to recess the lettering or design into the sidewall.
2. Background Information
Tire manufacturers have placed designs, logos, letters, and/or other patterns on the sidewalls of tires for many years. Such designs and lettering typically relate to the company that manufactured the tire. For instance, a company trademark may be used on the sidewall to identify the origin of the tire and to advertise the company's product. The tire companies thus desire that the lettering or design be visible and easily readable to a person from different angles and in different light conditions.
One manner of increasing the visibility of lettering and designs on a tire sidewall is to form the lettering or design from a rubber having a color different than the color of the tire sidewall. Tire sidewalls are typically black and it is known in the art to provide lettering formed from white, blue, yellow, or red rubber to allow the lettering to be readily differentiated from the tire sidewall. Although this method of increasing the visibility of the lettering is functional, it falls from consumer favor from time to time. Forming the sidewall with lettering in a rubber having a different color than the sidewall is also more expensive than simply forming the lettering directly in the sidewall material.
One style of lettering that has been used in the past is outlined letters formed in the black rubber of the sidewall. Such black-on-black letters can be difficult to see in some conditions. The reflectivity of the rubber that is used to form the sidewalls also adds to the visibility problem. It is thus desired in the art to provide a lettering structure or design structure that allows the lettering or designs to be formed directly in the tire sidewall while being readily visible to a person at different angles and in different light conditions.
One desirable lettering structure is to recess the letters into the sidewall. Such recessing creates black-on-black letters that are readily visible. It is, however, also known in the tire industry that it is undesirable to use a lettering or design structure that requires indentations to be formed in the tire sidewall. Design structures that have indentations that extend inwardly past the outer surface of the tire sidewall require a large portion of the design mold to be removed. The process of removing the large portions of the mold is time consuming and expensive. It is thus desirable to provide a lettering or design pattern that provides the desired increased visibility to the lettering or design while not requiring any portions of the structure of the lettering or pattern to extend inwardly from the outer surface of the tire sidewall.